在自定义对象数组中查找 属性 的条目

Question

我正在 Angular 2 中使用 Typescript 开发应用程序，但遇到了问题。我有一项服务可以获取像这样的问题数组

    export class Question {

    constructor(public id: number,
                public question_text: string,
                public answers: string[],
                public user_answer: string = "none") // default to none, update on user input

    {}
}

private questions: Question[] = [
    new Question(0, 
  'How often did you eat a portion of vegetables??', 
  ['Answer A','Answer B', 'Answer C', 'Answer D', 'Answer E', 'Answer F']),
    new Question(1, 
  'How often did you eat a portion of fruit?', 
  ['Answer A','Answer B', 'Answer C', 'Answer D', 'Answer E', 'Answer F']),

然后我有一个按钮，允许用户编辑问题（包括 ID 在内的所有数据）。我的 updateQuestion 看起来像这样：

updateQuestion(questionId: number, newQuestion: Question) {
   //Find question in array
   //Delete this entry
   //Add new question to array

}

我真的很难完成第一个任务：在数组中查找问题。我尝试了

的一些组合

this.questions.find(question => questionId == id) 

但那里的 id 未定义，我不确定如何访问它。

问题主要围绕在问题数组中找到正确的条目，其中 id = questionId

任何帮助将不胜感激！！

Answer 1

问题出在问题模型上。我已将问题模型更改为：

export class Question {

public _id: number;
public _question_text: string;
public _answers: string[];
public _user_answer: string;

constructor(public id: number,
            public question_text: string,
            public answers: string[],
            public user_answer: string = "none") // default to none, update on user input

{
    this._id = id;
    this._question_text = question_text;
    this._answers = answers;
    this._user_answer = user_answer;
}
}

然后是我的服务：

updateQuestion(questionId: number, newQuestion: Question) {
    const questionIndex = this.questions.findIndex(x => x._id == questionId);